From conventional group decision making to large-scale group decision making: What are the challenges and how to meet them in big data era? A state-of-the-art survey

•We propose a comprehensive review for large-scale group decision making.•We provide a bibliometric review for large-scale group decision making.•We summarize five challenges in large-scale group decision making.•We review main applications in large-scale group decision making.•We provide some important future directions for large-scale group decision making.